I've since got it to work on Xenial, but the app doesn't work correctly: the File, Edit, ... menu options don't work, for instance.
From my ever-growing notes, i got it to work by compiling pygobject-3.20.1.tar.xz, with
export GI_LIBS="-L/usr/lib/x86_64-linux-gnu -lglib-2.0"export GI_CFLAGS="-I/usr/include/glib-2.0 -I/usr/include/glib-2.0/include"export PYCAIRO_CFLAGS="-I/usr/include/pycairo"export CPPFLAGS="-I/usr/include/gobject-introspection-1.0"./configure --prefix=${PWD}/build/linux/x86_64 --enable-static --enable-shared --with-python=python2 but i'm not sure that's the path i followed and i was in a temporary directory.
Anyway, now i'm having the same issue in an windows vm.